package com.webserver.core;

import com.webserver.http.HttpRequest;
import com.webserver.http.HttpResponse;

import java.io.File;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 *  用于处理请求
 */
public class DispatcherServlet {
    public void service(HttpRequest request, HttpResponse response){
        String path  = request.getUri();
        File file = new File("./webapps"+path);
        if(file.exists()&&file.isFile()){
            //资源存在
            response.setEntity(file);
            /*
            1：通过file获取浏览器实际请求的资源的文件名
            2：根据文件名截取后缀名
            3：根据后缀名设置Content-Type对应的值（http.txt找对应的）
             */

            Map<String,String> mimeMapping = new HashMap();
            mimeMapping.put("html","text/html");
            mimeMapping.put("css","text/css");
            mimeMapping.put("js","application/javascript");
            mimeMapping.put("png","image/png");
            mimeMapping.put("gif","image/gif");
            mimeMapping.put("jpg","image/jpeg");

            String fileName = file.getName();
            String ext = fileName.substring(fileName.lastIndexOf(".") + 1);
            String type = mimeMapping.get(ext);

            response.addHeader("Content-Type",type);
            response.addHeader("Content-Length",file.length()+"");

        }else{
            //资源不存在
            response.setStatusCode(404);
            response.setStatusReason("NotFound");
            file = new File("./webapps/root/404.html");
            response.setEntity(file);
            response.addHeader("Content-Type","text/html");
            response.addHeader("Content-Length",file.length()+"");
        }

        response.addHeader("Server","WebServer");
    }
}
